In this book we see highlights of how Allah preserved the Sunnah by enabling the Companions and those after them to memorise, write down and pass on the statements of the Messenger (sallah Allahu alayhee wa sallam), and the descriptions of his way, as well as to continue the blessings of practising the Sunnah. Later, as the purity of the knowledge of the Sunnah became threatened, Allah caused the Muslim nation to produce outstanding individuals of incredible memory-skills and analytical expertise, who journeyed tirelessly to collect hundreds of thousands of narrations and distinguish the true words of precious wisdom of their Messenger (sallah Allahu alayhee wa sallam) from those corrupted by weak memories, from forgeries by unscrupulous liars, and from the statements of the enormous number of 'ulama', the Companions, and those who followed their way, who had taught in various centres of learning and helped to transmit the legacy of Muhammad (sallahu Allahu alayhee wa sallam) - all of this achieved through precise attention to the words narrated and detailed familiarity with the biographies of the thousands of reporters of Hadith. Actions being the best way to preserve teachings, the renewers of Islam also revived the practice of the blessed authentic Sunnah.